Apparatus for assembling tubes and liners in gun construction



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R. C. MORGAN ET AL.

APPARATUS FOR ASSEMBLING TUBES AND LIN ERS IN GUN CONSTRUCTION Filed Jan. 11 i922 Patented Nov. 4t, 1924.

REES C. MORGAN AND JOHN F. BELLY, OF BETIFILEHEM, PENNSYLVANIA, ASSIGNORS TO BETHLEHEM STEEL COMPANY, OF BETHLEHEM, PENNSYLVANIA, A CORPORA- TION OF PENNSYLVANIA.

APL ARATUS FOB ASSEMBLING TUBES AND LINERS IN GUN CONSTRUCTION.

Application filed January 11, 1922.

To all 1071mm it may concern:

Be it known that we, Runs C. MORGAN and J 01m F. PELLY, citizens of the United States, and residing at Bethlehem, county of Lehigh, State of Pennsylvania, respectively, have invented certain new and useful Tm provcments in Apparatus for Assembling Tubes and Liners in Gun Construction, of which the following is a specification.

It has heretofore been a standard practice in assembling liners in guns of large caliber to employ the shinka'ge method, in which the liner, which has an outside diameter greater than the inside diameter of the cylinder or tube into which it is to be placed, is kept in a relatively cool condition while the tube is expanded by heat until its inner diameter is such that it may be readily dropped over the liner, which has been previously coated with a lubricant. As the tube cools it contracts and firmly grips the liner, compressng the same, and shortening its inner diameter. The amount of this shortening is known as the compression caused by the assembling operation. In gun manufacture it is requisite that this compression be within certain limits, corresponding to certain compressive unit stresses in the wall of the liner.

The amount of this compression is not only dependent upon the shrinkage allowance, which is the amount by which the outer diameter of the liner exceeds the original inner diameter of the outer tube or cylinder, but is also affected by the manner in which the two concentric cylinders become frictionally bound together in the shrinkage process. it has been found that in manufacturing guns, particularly guns of large caliber, that rarely two guns when assembled have the same amount of compression although the dimensions and shrinkage allowances of the original cylinders were the same in each case. This undesirable uncertainty in the compression obtained is, for a given quality of steel, partly because of the tendency of the tube or outer cylinder to contract longitudinally as well as radially and to therefore grip and simultaneously contract the liner both radially and longitudinally. This long itudinal contraction of the liner afl'ects the radial compression thereof in a manner and to a degree-which cannot be accurately estima d. b e eleee i $eria1 No. 528,574.

It is an object of this invention therefore to provide an apparatus for assembling liners in tubes by shrinkage in which the longitudinal shortening of the liner and the result ing longitudinal compression stresses therein are largely avoided. This object is accomplished by providing means for positively holding the liner against longitudinal contraction in assembling so that the contracting tube or outer cylinder firmly grips as it cools, a liner the length of which cannot shorten as the tube shortens in cooling, which would otherwise be the natural result, the tube being universally thicker and stronger and well able toovercome the resistance of the liner. In guns assembled by this new apparatus longitudinal contraction or longitudinal compressive stresses in the liner are avoided or rendered negligible and the compressions actually obtained are more nearly equal to the theoretical compressions desired.

In actual practice it has been found advantageous to not only positively prevent the liner from being longitudinally contracted by the tube but to actually stretch the liner by power meansand the apparatus is not only designed and constructed 'to prevent longitudinal contraction ofthe liner as the tube contracts but also to exert any stretching force desired.

It is practically a universal practice also in manufacturing large caliber guns to form the liner with forwardingly facing annular shoulders at one or more points along its outer surface and these forwardly facing shoulders fit against, when the assembly has been completed, corresponding rearwardly facing annular shoulders on the interior wall of the tube or outer cylinder. The abutting shoulders constitute means for preventing creeping of the liner toward the muzzle cud infiring, under the action of the projectiles passing therethrough. In spite of most careful heatingand assembling it has beenfound in practice extremely diflicult to firmly seat the corresponding shoulders of the tube and liner so that they finally occup the correctrelative position. Difficulties of this character are increased when 'ap-lurality of pairs of such shoulders are to be seated, as in large caliber guns, the non-seating of the shoulders being caused by the gripping of the liner by the contracting tube that at points die;

tant from and in front of, the shoulders, for instance, near the muzzle end, being obvious that it the two cylinders should first bind together nearthe nuzzle end that as the tube contracts longitudinally the corresponding shoulders will become more and more separated instead of being forcibly driven together.

It is a further Object of this invention therefore to provide an apparatus whereby the corresponding shoulders of the cylinders in b on y e e-t cl-diir 11sthe eee mb y of .tl gun, after which hey are inuintained in t i Q eeie u e e i ie e el grip of theouter cylinder on the inner. In this 7 er the d ,ining force engag en be wee hem, wh reby t y a prese ed teem rota ing ela e y to r a h e =-Wh= el of -en occur n la g ea ns due to the tangential force exerted by to th lif i g.- Ehi effe is realized :;by ,ongitt i ng to lubricate the icon t: 'ng surfaces ,of the tube and liner tor a considerable distance near the muzzle ends thereod and ,by iutili hrg the power apparatus in assembling to .oyerconie the resistance c.- ieued l th led-. of lubricant, o bring the cylinders into proper nelatiye position. l ihhen the assembly is completed the cylinde il re s the t ndency towa r la v etet e tench m r s ns y than when lnbricant is p sent at this section. By the use of power of rd the eb e'e 1e 11;

' e i on 1 f e l-pr r r a semb ies 1- T if no new il i w re .enirl y l- One iornrot the inven 'onis l w I h h e ee nn nyi g shearns and fully described i h a tel oi iug Perasrerh Th ni the fo l d is descr ed end cla med n our .copendingapplication Ser. No. 528,572 fi ed Jen ll, 11 22- In the drawings:

Q ee in se i e u and e y essen-sle sle ing, p

' trated in free ends tially diagra ninatically, for stretching the liner; and

2 is a sectional View of a tube and liner after assembly.

In the following description, and'in the claims it will be understood that the term tube includes either a single cylinder or a plurality otconcentric cylinders assembled together.

The apparatus illustrated comprises a column or shaft 10 adapted to extend through the bore of the liner, this shaft being secured a the br e end 10 -.11 We n eehenism i dicated ut l1, and biting iected to its other enda plus" 12 wl oh is screw th' v ;-he nuzzle ,end of he liner. :Pii'otally conn' "ed to the g-po l lechan' 1 11 are two 311128 o b rs 13,

mechanism hooked 130.

clamped o The jinech anis 1 WhiiQllHl known type, P iieferably hyc ed ,to .ei ec-t relative inoyen ien t he ween t r 13 an th ce t shaft 10.,-1i el s efl by the arrows in Figure 1.

lne e n hliese tube and l n -id inter o of the tube is first ;.finis hed aiter which the xte i Q thelie ri Prep red-t e s. K nkel e b ing ed d totl eeut r=d anieter o1 the liner, and the shoulders otthe liner and tube being properly located. The liner isthen placed in position .on the shaft 10 which is preferably yert icu-ll y disposed, and the plug 12 screwed into previously prepared threads in its n uzzleiend. "The liner is then painted with lubricant, in accordance with the universal custom, with the exception of a portion near its muzzle end, which is left unlubricated. The tube is then, or has been in .the meanwhile, l1eate1;l..to,adegree insuring the proper expansion so that there will he ainple clcarzoiee between its inner wall and the outer wall .of the liner for the purpose of assembly. I v

h t tube di t r m the u nac is the owere ev t e l r? it m uzzle to breech until it has reached a position such as illustrated in Figure 1 in which its lowerinost shoulder in contact with time lowerm 1- bree eheulde 1 t e li e mhil the upper correspon 1g .sl. i the ub d liner e et nlseneriledlb tube a dl b ug susp idec torn plug 12, and the liner 3 ill in the air. Upon the release of the power mechanism the tube and liner remain firmly gripped together with the various corresponding shoulders firmly seated and the liner either entirely without longitudinal stress or with a certain amount of tensional stress, depending upon the amount of power applied and the design of the respective cylinders.

By leaving a portion of the tube and liner near the muzzle end unlubricated and employing power means in the assembly, the two members are firmly gripped together and rotation of the liner in service is largely prevented.

It is obvious that numerous changes may be made in the design and arrangement of the parts of the invention, which is not limited in scope to the exact embodiment above described.

Having thus described our invention what we claim as new and desire to secure by Letters Patent is:

1. In apparatus for assembling aliner and a gun tube having cooperating holding means to prevent movement of the liner as a whole with respect to the tube in a muzzleend direction when the tube is placed around the liner, means for preventing shortening of the liner while the tube is being shrunk thereon comprising a compression member, means for securing the compression member to the muzzle end of the liner, and means for supporting the compression member from the breech end of the tube.

2. In apparatus for assembling a liner and a gun tube having cooperating abutment means near the breech end to prevent movement of the liner as a whole with respect to the tube in a muzzle-end direction when the latter is placed around the liner, means for preventing shortening of the liner while the tube is being shrunk thereon comprising a column member extending through the liner, means carried by the column member for attachment to the muzzle end of the liner, and power means supported from the breech end of the tube and acting on the column member to apply tension forces to the liner in a muzzle-end direction and to the tube in a breech-end direction.

3. In apparatus for assembling a liner and a gun tube having cooperating abutment means near the breech end toprevent movement of the liner as a whole with respect to the tube in a. muzzle-end direction when the latter is placed around the liner, means for preventing shortening of the liner while the tube is being shrunk thereon comprising a column member extending through the liner, means carried by the column member for attachment to the muzzle end of the liner,

power means connected to the column member, and means for securing the power means to the tube.

4. In apparatus for assembling a liner and a gun tube having cooperating abutment means near the breech end to prevent movetension forces to the liner in a muzzle-end direction and to the tube in a breech-end direction.

5. In apparatus for assembling a liner and a gun tube having cooperating abutment means near the breech end to prevent movement of the liner as a whole with respect to the tube in a muzzle-end direction when the latter is placed around the liner, means for preventing shortening of the liner While the tube is being shrunk thereon comprising a column member extending through the liner, means carried by the column member for attachment to the muzzle end of the liner, power means connected to the column member and extending beyond the breech end of the tube and liner, and swingable hooks carried by the power means for engagement over abutment means on the tube.

6. In apparatus for assembling a liner and a gun tube having cooperating abutment means near the breech end to prevent movement of the liner as a whole with respect to the tube in a muzzle-end direction when the latter is placed around the liner, means for preventing shortening of the liner while the tube is being shrunk thereon comprising a column member extending through the liner, means carried by the column member for attachment to the muzzle end of the liner, an abutment ring adapted to pass over the n1uzzle end of the tube and to rest against a shoulder on the latter near the breech end, said abutment ring having exterior hook engaging means, power means connected to the column member and extending beyond the breech end of the tube and liner, and swingable hooks carried by the power means for engagement with the hook engaging means of said abutment ring.

In testimony whereof we hereunto afix our signatures.

REES C. MORGAN. JOHN F. PELLY. 

